/*
 * Copyright 1999-2101 Alibaba Group.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package com.alibaba.fastjson.serializer;

import java.io.IOException;
import java.lang.reflect.Type;
import java.util.LinkedHashMap;
import java.util.Map;
import java.util.SortedMap;
import java.util.TreeMap;

import com.alibaba.fastjson.JSON;

/**
 * @author wenshao<szujobs@hotmail.com>
 */
public class MapSerializer implements ObjectSerializer {

	public static MapSerializer instance = new MapSerializer();

	@SuppressWarnings({ "rawtypes", "unchecked" })
	public void write(JSONSerializer serializer, Object object, Object fieldName, Type fieldType) throws IOException {
		SerializeWriter out = serializer.getWriter();

		if (object == null) {
			out.writeNull();
			return;
		}

		Map<?, ?> map = (Map<?, ?>) object;

		if (out.isEnabled(SerializerFeature.SortField)) {
			if ((!(map instanceof SortedMap)) && !(map instanceof LinkedHashMap)) {
				try {
					map = new TreeMap(map);
				} catch (Exception ex) {
					// skip
				}
			}
		}

		if (serializer.containsReference(object)) {
			serializer.writeReference(object);
			return;
		}

		SerialContext parent = serializer.getContext();
		serializer.setContext(parent, object, fieldName);
		try {
			out.write('{');

			serializer.incrementIndent();

			Class<?> preClazz = null;
			ObjectSerializer preWriter = null;

			boolean first = true;

			if (out.isEnabled(SerializerFeature.WriteClassName)) {
				out.writeFieldName(JSON.DEFAULT_TYPE_KEY);
				out.writeString(object.getClass().getName());
				first = false;
			}

			for (Map.Entry entry : map.entrySet()) {
				Object value = entry.getValue();

				Object entryKey = entry.getKey();

				if (entryKey == null || entryKey instanceof String) {
					String key = (String) entryKey;

					if (!FilterUtils.applyName(serializer, object, key)) {
						continue;
					}

					if (!FilterUtils.apply(serializer, object, key, value)) {
						continue;
					}

					key = FilterUtils.processKey(serializer, object, key, value);
					value = FilterUtils.processValue(serializer, object, key, value);

					if (value == null) {
						if (!serializer.isEnabled(SerializerFeature.WriteMapNullValue)) {
							// 打开假的null值写入，使输出到字符串，即JsonObject。getString时可读取null,为null容器初始化的前提处理
							// by ylq at 20160301
							// continue;
						}
					}

					if (!first) {
						out.write(',');
					}

					if (out.isEnabled(SerializerFeature.PrettyFormat)) {
						serializer.println();
					}
					out.writeFieldName(key, true);
				} else {
					if (!first) {
						out.write(',');
					}

					serializer.write(entryKey);
					out.write(':');
				}

				first = false;

				if (value == null) {
					out.writeNull();
					continue;
				}

				Class<?> clazz = value.getClass();

				if (clazz == preClazz) {
					preWriter.write(serializer, value, entryKey, null);
				} else {
					preClazz = clazz;
					preWriter = serializer.getObjectWriter(clazz);

					preWriter.write(serializer, value, entryKey, null);
				}
			}
		} finally {
			serializer.setContext(parent);
		}

		serializer.decrementIdent();
		if (out.isEnabled(SerializerFeature.PrettyFormat) && map.size() > 0) {
			serializer.println();
		}
		out.write('}');
	}
}
